Obesity is an independent prognostic variable in colon cancer survivors

Post-diagnosis adiposity and colorectal cancer prognosis: A Global Cancer Update Programme (CUP Global) systematic literature review and meta-analysis

The adiposity influence on colorectal cancer prognosis remains poorly characterised. We performed a systematic review and meta-analysis on post-diagnosis adiposity measures (body mass index [BMI], waist circumference, waist-to-hip ratio, weight) or their changes and colorectal cancer outcomes. PubMed and Embase were searched through 28 February 2022. Random-effects meta-analyses were conducted when at least three studies had sufficient information. The quality of evidence was interpreted and graded by the Global Cancer Update Programme (CUP Global) independent Expert Committee on Cancer Survivorship and Expert Panel. We reviewed 124 observational studies (85 publications). Meta-analyses were possible for BMI and all-cause mortality, colorectal cancer-specific mortality, and cancer recurrence/disease-free survival. Non-linear meta-analysis indicated a reverse J-shaped association between BMI and colorectal cancer outcomes (nadir at BMI 28 kg/m2). The highest risk, relative to the nadir, was observed at both ends of the BMI distribution (18 and 38 kg/m2), namely 60% and 23% higher risk for all-cause mortality; 95% and 26% for colorectal cancer-specific mortality; and 37% and 24% for cancer recurrence/disease-free survival, respectively. The higher risk with low BMI was attenuated in secondary analyses of RCTs (compared to cohort studies), among studies with longer follow-up, and in women suggesting potential methodological limitations and/or altered physiological state. Descriptively synthesised studies on other adiposity-outcome associations of interest were limited in number and methodological quality. All the associations were graded as limited (likelihood of causality: no conclusion) due to potential methodological limitations (reverse causation, confounding, selection bias). Additional well-designed observational studies and interventional trials are needed to provide further clarification.

Mendelian randomization unraveled: gender-specific insights into obesity-related phenotypes and colorectal cancer susceptibility

Objective

Evidence has been increasingly pointing towards a potential link between phenotypes related to obesity and the incidence of colorectal cancer. However, confirming this as a direct causal connection remains elusive. This investigation aims to elucidate the causative links between obesity-associated phenotypes and the incidence of colorectal cancer.

Methods

Employing the Two Sample Mendelian Randomization (TwoSampleMR) R package, analyses were conducted using Mendelian randomization (MR) to discern potential causative links between obesity categories sourced from both the Institute for Education and University (IEU) Open GWAS Project and Zenodo, and colorectal tumors (data obtained from IEU Open GWAS and FinnGen). For primary evaluations, the study utilized the Wald ratio and the Inverse Variance Weighting (IVW) methods, while the MR-Egger approach was integrated for sensitivity assessment. Bidirectional Mendelian Randomization (Bidirectional MR), as well as Linkage Disequilibrium (LD) Score Regression with well-imputed HapMap3 single nucleotide polymorphisms (SNPs), were additionally executed. Sensitivity assessments entailed IVW, MR-Egger methodologies to assess heterogeneity and pleiotropy, along with a leave-one-out strategy. Instrumental variables were chosen judiciously based on predetermined P-value thresholds and F-statistics.

Results

Results from MR evaluations did not identify a clear causative link between BMI and colorectal malignancy. Conversely, both measures of obesity, the Waist-Hip Ratio (WHR) and its adjusted form for BMI (WHRadjBMI), displayed a connection to increased risk of colorectal cancer, especially prominent among female subjects. Reverse MR analyses dismissed potential reverse causality between colorectal malignancies and obesity. A significant genetic interplay was observed between WHR, WHRadjBMI, and colorectal cancer instances. Ensuing MR probes spotlighted inflammatory bowel ailment as a protective factor, while salad intake was indicated as a potential risk concerning colorectal malignancies. Sensitivity reviews, which included tests for both pleiotropy and heterogeneity, validated the robustness of the MR findings.

Conclusion

Findings from this research indicate that specific obesity-related parameters, notably WHR and WHRadjBMI, carry a causal relationship with an elevated colorectal cancer risk. The impact is distinctly more evident among females. Such insights might be pivotal for public health deliberations, hinting that individuals boasting a high WHR might necessitate intensified colorectal cancer screenings.

Body mass index, weight change, and cancer prognosis: a meta-analysis and systematic review of 73 cohort studies

BACKGROUND

Identifying the association between body mass index (BMI) or weight change and cancer prognosis is essential for the development of effective cancer treatments. We aimed to assess the strength and validity of the evidence of the association between BMI or weight change and cancer prognosis by a systematic evaluation and meta-analysis of relevant cohort studies.

METHODS

We systematically searched the PubMed, Web of Science, EconLit, Embase, Food Sciences and Technology Abstracts, PsycINFO, and Cochrane databases for literature published up to July 2023. Inclusion criteria were cohort studies with BMI or weight change as an exposure factor, cancer as a diagnostic outcome, and data type as an unadjusted hazard ratio (HR) or headcount ratio. Random- or fixed-effects models were used to calculate the pooled HR along with the 95% confidence interval (CI).

RESULTS

Seventy-three cohort studies were included in the meta-analysis. Compared with normal weight, overweight or obesity was a risk factor for overall survival (OS) in patients with breast cancer (HR 1.37, 95% CI 1.22-1.53; P < 0.0001), while obesity was a protective factor for OS in patients with gastrointestinal tumors (HR 0.67, 95% CI 0.56-0.80; P < 0.0001) and lung cancer (HR 0.67, 95% CI 0.48-0.92; P = 0.01) compared with patients without obesity. Compared with normal weight, underweight was a risk factor for OS in patients with breast cancer (HR 1.15, 95% CI 0.98-1.35; P = 0.08), gastrointestinal tumors (HR 1.54, 95% CI 1.32-1.80; P < 0.0001), and lung cancer (HR 1.28, 95% CI 1.22-1.35; P < 0.0001). Compared with nonweight change, weight loss was a risk factor for OS in patients with gastrointestinal cancer.

CONCLUSIONS

Based on the results of the meta-analysis, we concluded that BMI, weight change, and tumor prognosis were significantly correlated. These findings may provide a more reliable argument for the development of more effective oncology treatment protocols.

The impact of body mass index on survival endpoints among patients with metastatic urothelial carcinoma undergoing treatment with immune checkpoint inhibitors: A real-world multicenter analysis

BACKGROUND

Studies on the correlation between high body mass index (BMI) and extended survival among patients receiving immune checkpoint inhibitors (ICIs) have been made, although findings have shown variability. Our research explored the phenomenon of the "obesity paradox" in patients with metastatic urothelial carcinoma (mUC) undergoing treatment with ICIs.

MATERIALS AND METHODS

We conducted a retrospective analysis of patients diagnosed with mUC who received a minimum of one cycle of ICI treatment at two medical centers in Taiwan from September 2015 to January 2023. Features of patients' clinicopathologic factors, including age, sex, primary or metastatic location, treatment line, and BMI were examined. The primary outcome were overall survival (OS) and progression-free survival (PFS), which were assessed utilizing the Kaplan-Meier method. We employed the Cox-regression model to adjust for multiple covariates.

RESULTS

A total of 215 patients were included, with 128 (59.5%) being male, and the median age was 70 years. In the obese group (BMI ≥25 kg/m2 ), patients demonstrated significantly better median OS compared to the non-obese group (BMI <25 kg/m2 ) (21.9 vs. 8.3 months; p = 0.021). However, there was no significant difference in median PFS between the high and low BMI groups (4.7 vs. 2.8 months; p = 0.16). Post-hoc subgroup revealed a survival benefit from ICI treatment in male patients within the BMI ≥25 kg/m2 group (HR 0.49, 95% CI 0.30-0.81, p = 0.005).

CONCLUSION

Based on real-world data from the Asia-Pacific region, there appears to be a correlation between obesity and prolonged OS in patients receiving ICI treatment for mUC.

U-shaped association between body mass index and health-related quality of life impairment in Korean cancer survivors: a nationwide representative cross-sectional survey

PURPOSE

Although obesity is an important risk factor for cancer incidence, the effect of body mass index (BMI) on health-related quality of life (HRQoL) after cancer treatment remains unknown. This population-based cross-sectional study assessed different levels of BMI as an important factor associated with impaired HRQoL in long-term cancer survivors.

METHODS

The study enrolled 1104 cancer survivors from the fourth to seventh Korea National Health and Nutrition Examination Surveys (KNHANES 2007-2018) who were alive at least 5 years after their cancer diagnoses. The BMI was classified into four categories: < 20 (underweight), 20-22.9 (healthy weight), 23-24.9 (overweight), and ≥ 25 kg/m2 (obese). Impaired HRQoL was defined as the lowest quartile of European Quality of Life 5-Dimensions (EQ-5D) questionnaire scores.

RESULTS

Cancer survivors who were underweight or obese were more likely to report health problems on each dimension of the EQ-5D compared to the other BMI groups. In multivariate logistic regression analysis, the two extreme BMI categories were significantly associated with impaired HRQoL (BMI < 20 kg/m2: odds ratio [OR] = 1.73, 95% confidence interval [CI] = 1.08-2.86; BMI ≥ 25 kg/m2: OR = 2.14, 95% CI = 1.41-3.25; P trend = 0.049), especially in the gastrointestinal cancer group (P heterogeneity = 0.007). Moreover, the association between underweight/obese and impaired HRQoL showed a significant sex difference (P heterogeneity = 0.019).

CONCLUSIONS

The results of this study suggest that deviations from normal BMI, such as being underweight or obese, are negatively associated with HRQoL in long-term cancer survivors; to some extent, this may depend on cancer type and sex.

IMPLICATIONS FOR CANCER SURVIVORS

Reaching or maintaining a healthy weight should be emphasized for cancer survivors as a long-term goal even after cancer treatment.

The prognostic impact of BMI on colorectal cancer is stratified by tumor location

Purpose

Recent studies have revealed the contrasting prognostic roles of body mass index (BMI) and tumor location in colorectal cancer (CRC). Given that right- and left-sided CRC may exhibit inverse effects on outcome and body weight, the present study aimed to examine whether the prognostic value of BMI and tumor location could be reciprocally stratified.

Methods

This prospective, observational study recruited 4,086 patients diagnosed with stage III CRC from five independent clinical centers in China. The association of patients’ outcomes with BMI and tumor location was evaluated hierarchically by Kaplan–Meier and Cox proportional-hazards models.

Results

Although BMI was not associated with overall outcome, the association was significantly modified by tumor location. Among left-sided tumors, obesity and overweight were significantly associated with adverse overall survival (OS) and disease-specific survival (DSS). In contrast, among right-sided tumors, overweight was significantly associated with more favorable OS and DSS compared with the normal-weight group. The association of survival with tumor location did not reach statistical significance. However, hierarchical analysis by BMI revealed that left-sided tumors were associated with more favorable outcomes in the normal-weight group, while there was no statistically significant difference in the overweight or obese group.

Conclusions

BMI and tumor location may have opposing effects on CRC prognosis, when stratified by each other, after adjusting for other known prognostic factors. These findings are the first to show the interactive prognostic impact of BMI and tumor location, which could be relevant to the stratification of patient management.

Association of Prediagnosis Obesity and Postdiagnosis Aspirin With Survival From Stage IV Colorectal Cancer

IMPORTANCE

The potential relationship between obesity and colorectal cancer (CRC) outcome is poorly understood in patients with late-stage disease. Increased body mass index may negate aspirin use for cancer prevention, but its role as a factor on the effectiveness of postdiagnosis aspirin use is unclear.

OBJECTIVE

To evaluate how prediagnosis obesity and postdiagnosis aspirin use may be associated with overall survival in patients with late-stage colorectal cancer.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used self-reported data from patients with metastatic or treatment-refractory disease who consented to a clinical protocol at MD Anderson Cancer Center, a large US cancer treatment center. Patients were enrolled between 2010 and 2018 and followed up for mortality through July 2020. Analyses were conducted through March 2022.

EXPOSURES

Body mass index in the decade prior to initial diagnosis and regular aspirin use at survey completion.

MAIN OUTCOMES AND MEASURES

Overall survival was measured from stage IV diagnosis until death or last follow-up. Cox proportional hazards models were constructed to estimate associations of prediagnosis obesity and postdiagnosis aspirin use with overall survival.

RESULTS

Of 656 patients included in this analysis, 280 (42.7%) were women, 135 (20.6%) were diagnosed with CRC before age 45 years, 414 (63.1%) were diagnosed between ages 45 and 65 years, and 107 (16.3%) were diagnosed at 65 years or older; 105 patients (16.0%) were Black or Hispanic, and 501 (76.4%) were non-Hispanic White. Controlling for age, sex, race, stage at initial diagnosis, and weight change between prediagnosis and survey date, patients with obesity in the decade prior to CRC diagnosis had significantly higher likelihood of death (hazard ratio, 1.45; 95% CI, 1.11-1.91) compared with those with normal prediagnosis body mass index. Furthermore, only patients with normal prediagnosis body mass index experienced significant survival benefit with postdiagnosis aspirin use (hazard ratio, 0.59; 95% CI, 0.39-0.90).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, our findings suggest potentially differential tumor development in the long-term physiologic host environment of obesity. Confirmation and further evaluation are needed to determine whether prediagnosis body mass index may be used to estimate the benefit from postdiagnosis aspirin use.

Race, age, and sex differences on the influence of obesity on colorectal cancer sidedness and mortality: A national cross‐sectional study

BACKGROUND AND OBJECTIVES

Colorectal cancer (CRC) sidedness is recognized as a prognostic factor for survival; left-sided colorectal cancer is associated with better outcomes than right-sided colon cancer (RsCC). We aimed to evaluate the influence of obesity on CRC sidedness and determine how race, age, and sex affect mortality among overweight and obese individuals.

METHODS

A survey-weighted analysis was conducted using data obtained from the National Inpatient Sample between 2016 and 2019.

RESULTS

Of the 24 549 patients with a diagnosis of CRC and a reported body mass index (BMI), 13.6% were overweight and 49.9% were obese. The race distribution was predominantly non-Hispanic Whites (69.7%), followed by Black (15.6%), Hispanic (8.7%), and other race (6.1%). Overweight (BMI: 25-29.9) and obese (BMI: ≥30) individuals were more likely to have RsCC (adjusted OR [aOR] = 1.28; 95% CI: 1.17-1.39, p < 0.001 and aOR = 1.45; 95% CI: 1.37-1.54, p < 0.001, respectively). Obese Black individuals were more likely to have RsCC as compared to their White counterparts (aOR = 1.23; 95% CI: 1.09-1.38).

CONCLUSIONS

Obesity is associated with an increased risk of RsCC. In addition, racial disparities in CRC sidedness and outcomes are most pronounced among obese patients.

Obesity, cancer risk, and time-restricted eating

Obesity and the associated metabolic syndrome is considered a pandemic whose prevalence is steadily increasing in many countries worldwide. It is a complex, dynamic, and multifactorial disorder that presages the development of several metabolic, cardiovascular, and neurodegenerative diseases, and increases the risk of cancer. In patients with newly diagnosed cancer, obesity worsens prognosis, increasing the risk of recurrence and decreasing survival. The multiple negative effects of obesity on cancer outcomes are substantial, and of great clinical importance. Strategies for weight control have potential utility for both prevention efforts and enhancing cancer outcomes. Presently, time-restricted eating (TRE) is a popular dietary intervention that involves limiting the consumption of calories to a specific window of time without any proscribed caloric restriction or alteration in dietary composition. As such, TRE is a sustainable long-term behavioral modification, when compared to other dietary interventions, and has shown many health benefits in animals and humans. The preliminary data regarding the effects of time-restricted feeding on cancer development and growth in animal models are promising but studies in humans are lacking. Interestingly, several short-term randomized clinical trials of TRE have shown favorable effects to reduce cancer risk factors; however, long-term trials of TRE have yet to investigate reductions in cancer incidence or outcomes in the general population. Few studies have been conducted in cancer populations, but a number are underway to examine the effect of TRE on cancer biology and recurrence. Given the simplicity, feasibility, and favorable metabolic improvements elicited by TRE in obese men and women, TRE may be useful in obese cancer patients and cancer survivors; however, the clinical implementation of TRE in the cancer setting will require greater in-depth investigation.

Muscle-to-tumor crosstalk: The effect of exercise-induced myokine on cancer progression

Physical exercise has gradually become a focus in cancer treatment due to its pronounced role in reducing cancer risk, enhancing therapeutic efficacy, and improving prognosis. In recent decades, skeletal muscles have been considered endocrine organs, exerting their biological functions via the endocrine, autocrine, and paracrine systems by secreting various types of myokines. The amount of myokines secreted varies depending on the intensity, type, and duration of exercise. Recent studies have shown that muscle-derived myokines are highly involved the effects of exercise on cancer. Multiple myokines, such as interleukin-6 (IL-6), oncostatin M (OSM), secreted protein acidic and rich in cysteine (SPARC), and irisin, directly mediate cancer progression by influencing the proliferation, apoptosis, stemness, drug resistance, metabolic reprogramming, and epithelial-mesenchymal transformation (EMT) of cancer cells. In addition, IL-6, interleukin-8 (IL-8), interleukin-15 (IL-15), brain-derived neurotrophic factor (BDNF), and irisin can improve obesity-induced inflammation by stimulating lipolysis of adipose tissues, promoting glucose uptake, and accelerating the browning of white fat. Furthermore, some myokines could regulate the tumor microenvironment, such as angiogenesis and the immune microenvironment. Cancer cachexia occurs in up to 80% of cancer patients and is responsible for 22%-30% of patient deaths. It is characterized by systemic inflammation and decreased muscle mass. Exercise-induced myokine production is important in regulating cancer cachexia. This review summarizes the roles and underlying mechanisms of myokines, such as IL-6, myostatin, IL-15, irisin, fibroblast growth factor 21 (FGF21) and musclin, in cancer cachexia. Through comprehensive analysis, we conclude that myokines are potential targets for inhibiting cancer progression and the associated cachexia.

Outcomes of right-sided and left-sided colon cancer after curative resection

The right and left side of the colon derived from the midgut and hindgut, respectively. Previous studies have reported different characteristics of right-sided colon cancer (RCC) and left-sided colon cancer (LCC), but oncological outcomes remain unclear. This study compared the outcomes of RCC and LCC. This retrospective study included 1017 patients who received curative colectomy for stage I-III colon cancer at a single institute between August 2008 and December 2019. Overall survival (OS) and time to recurrence (TTR) were analyzed as outcome measurements. No significant difference in the OS or TTR of patients with RCC and LCC were observed. In subgroup analysis, RCC was associated with shorter TTR than LCC in stage II colon cancer (HR 2.36, 95% confidence interval 1.24–4.48, p < 0.01). Multivariate analysis demonstrated that right sidedness, R1 resection, low body mass index (BMI) and adjuvant chemotherapy were independent factors for poor prognosis for stage II colon cancer. Low BMI, perineural invasion, higher T stage and N2 stage were independent factors for poor prognosis for stage III colon cancer. The results were confirmed by multivariate analysis after propensity score matching. Our study revealed that RCC was an independent risk factor for recurrence in stage II colon cancer.

The obesity paradox in patients with colorectal cancer: a systematic review and meta-analysis

CONTEXT

Obesity is widely regarded as an established risk factor for colorectal cancer (CRC). However, recent studies have shown that lower mortality and better cancer-specific survival were observed in CRC patients with elevated body mass index (BMI), an example of the obesity paradox, which is the inverse correlation between obesity and mortality in some populations.

OBJECTIVE

The aim of this systematic review and meta-analysis was to investigate the association between BMI and CRC outcomes.

DATA SOURCES

PubMed, Web of Science, MEDLINE, the Cochrane Library, and Embase databases were searched for relevant articles published from inception to December 31, 2020.

STUDY SELECTION

Studies comparing the prognosis of CRC patients with obesity or overweight with that of normal-weight CRC patients were eligible.

DATA EXTRACTION

Data were extracted by 2 reviewers independently; differences were resolved by a third reviewer. BMI was classified according to WHO categories.

DATA ANALYSIS

To assess the prognostic effects of different BMI categories in CRC patients, hazard ratios and 95%CIs of overall survival, disease-free survival, and cancer-specific survival were extracted from included articles.

RESULTS

Sixteen studies (55 391 patients in total) were included. Higher BMI was significantly associated with more favorable CRC outcomes. Compared with normal-weight patients, underweight patients had worse overall survival (HR = 1.26; 95%CI, 1.15-1.37) and disease-free survival (HR = 1.19; 95%CI, 1.11-1.27, while patients with overweight had better overall survival (HR = 0.92; 95%CI, 0.86-0.99), disease-free survival (HR = 0.96; 95%CI, 0.93-1.00), and cancer-specific survival (HR = 0.86; 95%CI, 0.76-0.98). Patients with morbid obesity had worse overall survival (HR = 1.12; 95%CI, 1.02-1.22) and disease-free survival (HR = 1.15; 95%CI, 1.07-1.24) than normal-weight patients. There was no significant difference in cancer-specific survival between patients with obesity (HR = 0.94; 95%CI, 0.76-1.16) and patients with normal weight, nor between patients with underweight and patients with normal weight (HR = 1.14; 95%CI, 0.82-1.58).

CONCLUSIONS

CRC patients with a higher BMI appear to have reduced mortality compared with normal-weight CRC patients, even though higher BMI/obesity is an established determinant for the development of CRC.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42020202320.

'Weighing' Losses and Gains: Evaluation of the Healthy Lifestyle Modification After Breast Cancer Pilot Program

Objectives

This pilot study sought to develop and evaluate a novel online group-based intervention (Healthy Lifestyle Modification after Breast Cancer; HLM-ABC) to help breast cancer survivors (BCSs) make healthy lifestyle changes intended to yield not only beneficial physical outcomes (i.e., weight loss, reduced body mass index) but also greater behavioral (e.g., increased physical activity, healthier eating), and psychosocial well-being (e.g., self-efficacy, motivation, body image).

Methods

An exploratory single-arm, mixed-method triangulation design was employed to evaluate the feasibility and preliminary effectiveness of the HLM-ABC intervention for overweight BCSs. Fourteen women participated in the 10-week intervention and completed quantitative measures of the above-mentioned outcomes at baseline, post-treatment, 6-month, and 12-month follow-up time points. Qualitative data were obtained post-treatment via semi-structured interviews and a treatment satisfaction questionnaire.

Results

Participants lost an average of 2.83% of their baseline weight (M = 196.65; SD = 38.59) by 1-year follow-up (M = 191.29; SD = 33.91), equal to a small effect size (d = -0.37). Despite achieving only modest weight loss, participants achieved meaningful gains in the form of increased physical activity (d = 0.2), discovery of gratifying movement, more intuitive eating habits (d = 1.12), greater bodily and emotional awareness, and positive shifts in beliefs about being able to make healthy choices regarding food (d = 0.63) and physical activity (d = 0.38). Furthermore, they demonstrated a slight improvement in body image (d = 0.36) and described feeling more self-compassionate, empowered, and acknowledging of variables beyond control (i.e., hormonal therapy, unsatisfactory surgery) that can present barriers to change.

Conclusion

After completing a 10-week online program, participants achieved meaningful and lasting changes on a number of healthful indicators, even when this did not correspond with a significant reduction in weight. Findings highlight the complex, multifaceted nature of "health" and lend support for promotion of healthier lifestyle following cancer treatment that encompasses not only physical weight, but also behavior, psychosocial well-being, and (often unmodifiable) circumstances such as life-preserving hormonal treatments.

Dahuang Fuzi Baijiang Decoction restricts progenitor to terminally exhausted T cell differentiation in colorectal cancer

Obesity contributes to about 30% incidence of colorectal cancer (CRC). Obese tumor microenvironment compromises anti-tumor immunity by eliciting exhausted T cells (Tex). Hypothesizing that Dahuang Fuzi Baijiang Decoction (DFB), a combined classical prescription from "Synopsis of Golden Chamber", modulates the differentiation of tumor-infiltrating CD8⁺ T cells, we firstly demonstrate that DFB regresses tumor growth in high-fat diet induced obese mice via expanding PD-1^int TIM3^- and restricting PD-1^hi TIM3⁺ subset. TCF1 is highly expressed in PD-1^int TIM3^- subset but is absent in PD-1^hi TIM3⁺ cells. We next confirm that progenitor PD-1^int TCF⁺ cells robustly produce TNFɑ and IFNγ while terminally differentiated PD-1^int TCF⁺ cells have defects in generating TNFɑ. With transgenic ob/ob mice, we find that DFB produces cooperative efficacy with anti-PD-1 (ɑPD-1) by limiting PD-1^hi Tim3⁺ subset and amplifying PD-1^int TCF⁺ population. Finally, we define CCR2⁺ CD8⁺ subset as teminal Tex and identify that the differentiation from progenitor to terminal Tex is driven, at least in part, by CCL2/CCR2 axis. CCR2 inhibitor enhances the response to ɑPD-1 by promoting the counts of progenitor Tex. Altogether, DFB dampens CCL2 and preserves progenitor Tex in obese microenvironment to restrain CRC progression. These finds provide unambiguous evidence that traditional Chinese formula DFB can prevent tumor progression by modulating adaptive immunity and give rise to strong rationale for further clinical verification.

Prognostic Factors of Recurrence and Survival in Operated Patients with Colorectal Cancer

BACKGROUND: The recurrence of colorectal cancers is considered to be one of the greatest post-surgical complications that is affected by various factors. This study was designed to investigate the prognostic factors that affect the recurrence and survival of patients with colon and rectal cancers. METHODS: A retrospective study was performed on 380 patients with colorectal cancers who underwent surgery were enrolled in the study (152 patients with colon cancer and 228 patients with rectal cancer). Preoperative serum albumin level, type of surgery, tumor size, differentiation grade, proximal, distal and radial, and marginal involvement, the total number of excised lymph nodes, the number of involved lymph nodes, and tumor stage were recorded. Also, the incidences of recurrence and metastasis were recorded during the study. RESULTS: 380 patients with a mean age of 57.11 years were enrolled in the study. 152 patients with an average age of 57.57 years were diagnosed as having colon cancer. Recurrence and metastasis occurred in two patients (1.3%) and five patients (3.3%), respectively. 18 patients (11.8%) died because of colon cancer. 228 patients with a mean age of 56.81 had rectal cancer. Recurrence was seen in 19 patients (8.3%) and metastasis in 33 patients (14.5%). 38 patients (16.7%) died because of rectal cancer. Tumor size and involved lymph nodes were independent prognostic factors for the recurrence and metastases of colon cancer. Only involved lymph nodes were associated with death due to colon cancer. Independent prognostic factors for rectal cancer metastasis include serum albumin level and age. The total number of excised lymph nodes was the only predictor of tumor recurrence and death in rectal cancer. The median survival times of colon and rectal cancers were 90 and 110 months, respectively. CONCLUSION: The size of the tumor and the number of involved lymph nodes were independent prognostic factors for recurrence and metastasis of colon cancer. Also, the number of involved lymph nodes was associated with colon cancer-related deaths. In the case of rectal cancer, serum albumin levels and age predicted metastases. Only the total number of excised lymph nodes had a reverse relationship with recurrence and rectal cancer-related death.

Randomized trial of two artificial intelligence coaching interventions to increase physical activity in cancer survivors

Physical activity (PA) has numerous health benefits. Personalized coaching may increase adherence to PA recommendations, but it is challenging to deliver personalized coaching in a scalable manner. The objective of our study was to determine whether novel artificially intelligent (AI) coaching interventions increase PA among overweight or obese, physically inactive cancer survivors compared to a control arm that receives health information. We conducted a single-center, three-arm randomized trial with equal allocation to (1) voice-assisted AI coaching delivered by smart speaker (MyCoach), (2) autonomous AI coaching delivered by text message (SmartText), and (3) control. Data collection was automated via sensors and voice technology, effectively masking outcome ascertainment. The primary outcome was change in mean steps per day from baseline to the end of follow-up at 4 weeks. Of the 42 randomized participants, 91% were female, and 36% were Black; mean age was 62.1 years, and mean BMI was 32.9 kg/m². The majority were breast cancer survivors (85.7%). At the end of 4 weeks follow-up, steps increased in the MyCoach arm by an average of 3618.2 steps/day; the net gain in this arm was significantly greater [net difference = 3568.9 steps/day (95% CI: 1483–5655), P value <0.001] compared to control arm, and [net difference = 2160.6 steps/day (95% CI: 11–4310), P value 0.049] compared to SmartText. In conclusion, AI-based voice-assisted coaching shows promise as a practical method of delivering scalable, individualized coaching to increase physical activity in sedentary cancer survivors. Additional research is needed to replicate these findings in a broader population of cancer survivors and to investigate the effects of these interventions in the general population.

ClinicalTrials.gov Identifier: NCT03212079, July 11, 2017, https://clinicaltrials.gov/ct2/show/NCT03212079.

Lack of Concordance among Nutritional Diagnostic Methods in Newly Diagnosed Colorectal Cancer Patients

This study aimed to investigate the concordance of different nutritional assessment methods and the prevalence of inadequate nutritional status in newly diagnosed Colorectal cancer (CRC) patients. Cross sectional study was conducted in a public hospital in Alagoas, Brazil. Clinical, nutritional (patient-generated subjective global assessment [PG-SGA], body mass index [BMI], arm circumference [AC], triceps skinfold [TSF], arm muscle circumference [AMC]) and functional (handgrip strength [HGS]) data were collected from July 2017-January 2019. Of the 31 CRC patients with a mean age of 58.97 ± 14.96 years, 48.4% were elderly and 51.6% were female. TSF adequacy (80.8%) and PG-SGA (80.0%) revealed the highest prevalence of malnutrition. BMI identified the same prevalence of malnutrition and excess weight (30.0%). The concordance between PG-SGA and BMI (kappa = 0.086; p = 0.426) was slight, with fair HGS (kappa = 0.268; p = 0.124). PG-SGA and AC (kappa = 0.015; p = 0.99), TSF (kappa = 0.195; p = 0.558) and AMC adequacy (kappa = 0.142; p = 0.380) were poor. PG-SGA can diagnose malnutrition, even in those who are eutrophic/overweight, by other methods. Various methods do not show concordance with PG-SGA, confirming the need for both objective and subjective methods for better diagnosis of CRC patients.

Intermittent fasting in the prevention and treatment of cancer

Chronic caloric restriction (CR) has powerful anticarcinogenic actions in both preclinical and clinical studies but may be difficult to sustain. As an alternative to CR, there has been growing interest in intermittent fasting (IF) in both the scientific and lay community as a result of promising study results, mainly in experimental animal models. According to a survey by the International Food Information Council Foundation, IF has become the most popular diet in the last year, and patients with cancer are seeking advice from oncologists about its beneficial effects for cancer prevention and treatment. However, as discussed in this review, results from IF studies in rodents are controversial and suggest potential detrimental effects in certain oncologic conditions. The effects of IF on human cancer incidence and prognosis remain unknown because of a lack of high-quality randomized clinical trials. Preliminary studies suggest that prolonged fasting in some patients who have cancer is safe and potentially capable of decreasing chemotherapy-related toxicity and tumor growth. However, because additional trials are needed to elucidate the risks and benefits of fasting for patients with cancer, the authors would not currently recommend patients undergoing active cancer treatment partake in IF outside the context of a clinical trial. IF may be considered in adults seeking cancer-prevention benefits through means of weight management, but whether IF itself affects cancer-related metabolic and molecular pathways remains unanswered.

Correlation of Body Mass Index with Oncologic Outcomes in Colorectal Cancer Patients: A Large Population-Based Study

It has been acknowledged that excess body weight increases the risk of colorectal cancer (CRC); however, there is little evidence on the impact of body mass index (BMI) on CRC patients' long-term oncologic results in Asian populations. We studied the influence of BMI on overall survival (OS), disease-free survival (DFS), and CRC-specific survival rates in CRC patients from the administrative claims datasets of Taiwan using the Kaplan-Meier survival curves and the log-rank test to estimate the statistical differences among BMI groups. Underweight patients (<18.50 kg/m²) presented higher mortality (56.40%) and recurrence (5.34%) rates. Besides this, they had worse OS (aHR:1.61; 95% CI: 1.53-1.70; p-value: < 0.0001) and CRC-specific survival (aHR:1.52; 95% CI: 1.43-1.62; p-value: < 0.0001) rates compared with those of normal weight patients (18.50-24.99 kg/m²). On the contrary, CRC patients belonging to the overweight (25.00-29.99 kg/m²), class I obesity (30.00-34.99 kg/m²), and class II obesity (≥35.00 kg/m²) categories had better OS, DFS, and CRC-specific survival rates in the analysis than the patients in the normal weight category. Overweight patients consistently had the lowest mortality rate after a CRC diagnosis. The associations with being underweight may reflect a reverse causation. CRC patients should maintain a long-term healthy body weight.

Relationship between colonic diverticulosis and colon neoplasms in Japanese patients

BACKGROUND AND AIM

Colonic diverticulosis (CD) has been reported to be associated with presence of colon neoplasms (CNs) in Western patients, since most of the associated risk factors are common between them. However, such correlation has not been fully investigated in Asian patients. In this study, the association of CNs with CD was evaluated in a multicenter investigation.

METHODS

We enrolled 5633 patients who underwent both colonoscopy and esophagogastroduodenoscopy due to annual follow-up, screening for positive occult blood testing and abdominal symptoms between January 2016 and December 2017 at three institutions. The relationship between the presence of CNs and CD was investigated, and predictors for presence of CNs were determined by multivariate logistic analysis.

RESULTS

The enrolled patients consisted of 1799 (31.9%) with CD (average age 70.0 years, male 64.0%) and 3834 without CD (66.0 years, male 52.9%), with the prevalence of CNs in those groups 46.6% and 44.2%, respectively (P = 0.090). Predictors for early colon cancer were shown to be age (OR 1.02, 95% CI 1.01-1.04, P = 0.010), laxatives use (OR 1.76, 95% CI 1.17-2.64, P = 0.007), gastric neoplasms (OR 2.16, 95% CI 1.23-3.81, P = 0.008), and CD (OR 1.64, 95% CI 1.16-2.31, P = 0.005). Early colon cancer in the distal colon was most frequently detected in patients with right-sided CD (RR 2.50, P = 0.001).

CONCLUSION

In Japanese patients, early colon cancer was more frequently found in those with as compared to those without CD. The presence of CD may be an important indicator for an index colonoscopy examination to detect colon cancer. (Clinical-trial-registry: UMIN000038985).

Metabolic syndrome is a predictor of all site and liver-specific recurrence following primary resection of colorectal cancer: Prospective cohort study of 1006 patients

INTRODUCTION

Large epidemiological studies have demonstrated the link between metabolic syndrome and cancer development, including colorectal cancer. However, the influence of metabolic syndrome on disease progression is less well studied, particularly in the post-surgical setting. This study investigates the effect of metabolic syndrome on colorectal cancer recurrence (all-site and liver-specific) after curative surgery for Stage I-III disease.

MATERIALS AND METHODS

Consecutive patients who underwent curative resection for Stage I-III colorectal cancer in a single UK centre were prospectively recruited. Disease-free and overall survival with metabolic syndrome as a factor, were determined using the Kaplan-Meier technique. Hazard ratios for all-site and liver-specific recurrence were determined using univariable and multivariable Cox-regression models.

RESULTS

1006 patients were recruited and followed up for a median of 50 months (IQR 30-67). 177 patients (17.6%) met the criteria for metabolic syndrome. 245 patients (25.4%) developed recurrence, 161 (16.0%) of these had liver recurrence. The presence of metabolic syndrome was associated with a reduction in disease-free survival from 69 to 58 months (p < 0.001) and overall survival from 74 to 61 months (p < 0.001). Metabolic syndrome was an independent predictor of all-site (HR 1.76; p < 0.001) and liver-specific (HR 1.74; p = 0.01) recurrence.

CONCLUSION

Metabolic syndrome is a predictor of all-site and liver-specific recurrence after primary resection of stage I-III colorectal cancer.

Body mass index and body weight change during adjuvant chemotherapy in colon cancer patients: results from the AVANT trial

While obesity increases colorectal cancer incidence, there are inconsistent results in the prognostic role of obesity or body weight change on survival. This study investigated the prognostic impact of body weight and weight change in stage III or high risk stage II colon cancer patients. We used data from patients enrolled in the phase III AVANT trial. The AVANT trial investigated the efficacy of adding bevacizumab to standard adjuvant chemotherapy (FOFOX or XELOX). Weight change during the first 6 months of adjuvant chemotherapy was measured. Cox proportional hazard model was used to assess the prognostic influence of body weight and weight change. Among 3451 intention-to-treat population, body weight and weight change was measured in 3449 (99.9%) and 2455 (71.1%) patients, respectively. Among 2455 patients, 651 (26.5%) had weight gain over 5 kg and 179 (7.3%) had weight loss over 5 kg. Weight gain was more frequently observed in Asian and male. Neither baseline BMI nor weight change affected recurrence or survival in the Cox proportional hazard model.

Effects of body composition profiles on oncological outcomes and postoperative intraabdominal infection following colorectal cancer surgery

BACKGROUND

Anthropometric data as prognostic factors of colorectal cancer are promising but contradictory. The aim of this study was to assess the preoperative body composition profiles as predictive factors for postoperative, oncologic, and inflammation outcomes.

OBJECTIVES

We sought to assess the impact of body composition profiles on short- and long-term outcomes and on postoperative inflammatory response in a clinical setting for patients following curative intent surgery for colorectal cancer.

SETTING

University hopsital METHODS: We analyzed 122 patients from a prospective cohort (IMACORS) with colorectal cancer undergoing curative-intent surgery from 2011 to 2014. Musculature, total, visceral, and subcutaneous adiposity were measured from a preoperative CT scan and outcomes were compared between profiles.

RESULTS

Preoperative myopenia was an independent predictive factor of recurrence (HR = 3.3 95% CI = 1.6-6.9; P = .002) while subcutaneous adiposity was a protective factor (HR = .4 95% CI = .2-.9; P = .03). No anthropometric measurement was predictive of overall survival and postoperative intra abdominal infection was not determined by body composition profiles. Preoperative and D4 CRP levels were significantly higher in patients with subcutaneous adiposity.

CONCLUSIONS

Myopenia and subcutaneous adiposity seemed to have independent and opposite prognostic effects on recurrence. Muscle mass loss may represent a modifiable risk factor while the amount of subcutaneous adipose tissue reflects an energetic storage favorable to face this pathologic process.

The Role of Diet in Cancer Prevention and Chemotherapy Efficacy

Despite great advances in treatment, cancer remains a leading cause of death worldwide. Diet can greatly impact health, while caloric restriction and fasting have putative benefits for disease prevention and longevity. Strong epidemiological associations exist between obesity and cancer, whereas healthy diets can reduce cancer risk. However, less is known about how diet might impact cancer once it has been diagnosed and particularly how diet can impact cancer treatment. In the present review, we discuss the links between obesity, diet, and cancer. We explore potential mechanisms by which diet can improve cancer outcomes, including through hormonal, metabolic, and immune/inflammatory effects, and present the limited clinical research that has been published in this arena. Though data are sparse, diet intervention may reduce toxicity, improve chemotherapy efficacy, and lower the risk of long-term complications in cancer patients. Thus, it is important that we understand and expand the science of this important but complex adjunctive cancer treatment strategy.

Association of a Preoperative Leisure-Time Physical Activity With Short- and Long-term Outcomes of Patients Undergoing Curative Resection for Stage I to III Colorectal Cancer: A Propensity Score Matching Analysis

BACKGROUND

Physical activity might be directly or indirectly linked to the risk of colorectal cancer and the prognosis of patients with colorectal cancer.

OBJECTIVE

This study aimed to elucidate whether preoperative physical activity plays a role in reducing short-term postoperative complications and improving long-term survival of patients with colorectal cancer.

DESIGN

This was a retrospective analysis of prospectively collected data.

SETTINGS

This study was conducted at a department of colorectal surgery in a tertiary teaching hospital between January 1995 and December 2016.

PATIENTS

Patients who underwent curative resection for stage I to III primary colorectal cancer were enrolled. According to the preoperative leisure-time weekly metabolic equivalent of task values, patients were divided into 2 groups: the metabolic equivalent of task <12 group and the metabolic equivalent of task ≥12 group. A 1:1 propensity score matching was used to reduce imbalance and selection biases based on 6 covariates, namely, age, sex, BMI, tumor location, tumor stage, and adjuvant chemotherapy administration.

MAIN OUTCOME MEASURES

χ tests were used to analyze short-term postoperative complications. Kaplan-Meier analyses were used to evaluate disease-free survival and overall survival.

RESULTS

In the matched cohort patients, significant differences in overall postoperative complications and mortality were observed in favor of the metabolic equivalent of task ≥12 group, although there was no difference in any single item of postoperative morbidity. The results of the Kaplan-Meier analysis and log-rank test demonstrated a significant survival benefit in the metabolic equivalent of task ≥12 group compared with the metabolic equivalent of task <12 group both for disease-free and overall survival.

LIMITATIONS

This study is limited by its retrospective nature.

CONCLUSIONS

This single-institute study provides evidence of the association of preoperative leisure-time physical activity with short-term postoperative morbidity and mortality, as well as long-term survival. See Video Abstract at http://links.lww.com/DCR/B189. ASOCIACIÓN DE ACTIVIDAD FÍSICA DE TIEMPO LIBRE PREOPERATORIA CON RESULTADOS A CORTO Y LARGO PLAZO DE PACIENTES SOMETIDOS A RESECCIÓN CURATIVA POR CÁNCER COLORRECTAL EN ESTADIO I-III: UN ANÁLISIS DE COINCIDENCIA DE PUNTAJE DE PROPENSIÓN ANTECEDENTES: LA ACTIVIDAD FíSICA PUEDE ESTAR DIRECTA O INDIRECTAMENTE RELACIONADA CON EL RIESGO DE CÁNCER COLORRECTAL Y EL PRONÓSTICO DE LOS PACIENTES CON CÁNCER COLORRECTAL.: Este estudio tuvo como objetivo dilucidar si la actividad física preoperatoria desempeña un papel en la reducción de las complicaciones postoperatorias a corto plazo y en mejorar la supervivencia a largo plazo de los pacientes con cáncer colorrectal.Este fue un análisis retrospectivo de datos recolectados prospectivamente.Este estudio se realizó en un departamento de cirugía colorrectal en un hospital universitario terciario entre Enero de 1995 y Diciembre de 2016.Se incluyeron pacientes sometidos a resección curativa por cáncer colorrectal primario en estadio I-III. De acuerdo con el equivalente metabólico semanal en el tiempo libre de los valores de la tarea preoperatorio, los pacientes se dividieron en dos grupos: el equivalente metabólico del grupo de tarea <12 y el equivalente metabólico del grupo de tarea ≥ 12. Se utilizó una coincidencia de puntaje de propensión 1: 1 para reducir los desequilibrios y los sesgos de selección basados en seis covariables, principalmente, edad, sexo, índice de masa corporal, ubicación del tumor, estadio del tumor y administración de quimioterapia adyuvante.Las pruebas de Chi-cuadrado se utilizaron para analizar las complicaciones postoperatorias a corto plazo. Los análisis de Kaplan-Meier se utilizaron para evaluar la supervivencia libre de enfermedad y la supervivencia general.en los pacientes de la cohorte emparejada, se observaron diferencias significativas en las complicaciones postoperatorias generales y la mortalidad a favor del equivalente metabólico del grupo de tareas ≥ 12, aunque no hubo diferencias en ningún elemento único de morbilidad postoperatoria. Los resultados del análisis de Kaplan-Meier y la prueba de log-rank demostraron un beneficio de supervivencia significativo en el equivalente metabólico del grupo tarea ≥ 12 en comparación con el equivalente metabólico del grupo tarea <12 tanto para la supervivencia libre de enfermedad como para la supervivencia general.Este estudio está limitado por su naturaleza retrospectiva.Este estudio de instituto único proporciona evidencia de la asociación de la actividad física preoperatoria en el tiempo libre con la morbilidad y mortalidad postoperatorias a corto plazo, así como la supervivencia a largo plazo. Consulte Video Resumen en http://links.lww.com/DCR/B189. (Traducción-Dr. Yesenia Rojas-Kahlil).

Expression of Genes Related to Lipid Handling and the Obesity Paradox in Melanoma: Database Analysis

Background

Publicly available genomic and transcriptomic data in searchable databases allow researchers to investigate specific medical issues in thousands of patients. Many studies have highlighted the role lipids play in cancer initiation and progression and reported nutritional interventions aimed at improving prognosis and survival. Therefore, there is an increasing interest in the role that fat intake may play in cancer. It is known that there is a relationship between BMI and survival in patients with cancer, and that there is an association between a high-fat diet and increased cancer risk. In some cancers, such as colorectal cancer, obesity and high fat intake are known to increase the risk of cancer initiation and progression. On the contrary, in patients undergoing treatment for melanoma, a higher BMI unexpectedly acts as a protective factor rather than a risk factor; this phenomenon is known as the obesity paradox.

Objective

We aimed to identify the molecular mechanism underlying the obesity paradox, with the expectation that this could indicate new effective strategies to reduce risk factors and improve protective approaches.

Methods

In order to determine the genes potentially involved in this process, we investigated the expression values of lipid-related genes in patients with melanoma or colorectal cancer. We used available data from 2990 patients from 3 public databases (IST [In Silico Transcriptomics] Online, GEO [Gene Expression Omnibus], and Oncomine) in an analysis that involved 3 consecutive validation steps. Of this group, data from 1410 individuals were analyzed in the IST Online database (208 patients with melanoma and 147 healthy controls, as well as 991 patients with colorectal cancer and 64 healthy controls). In addition, 45 melanoma, 18 nevi, and 7 healthy skin biopsies were analyzed in another database, GEO, to validate the IST Online data. Finally, using the Oncomine database, 318 patients with melanoma (312 controls) and 435 patients with colorectal cancer (445 controls) were analyzed.

Results

In the first and second database investigated (IST Online and GEO, respectively), patients with melanoma consistently showed significantly (P<.001) lower expression levels of 4 genes compared to healthy controls: CD36, MARCO, FABP4, and FABP7. This strong reduction was not observed in patients with colorectal cancer. An additional analysis was carried out on a DNA-TCGA data set from the Oncomine database, further validating CD36 and FABP4.

Conclusions

The observed lower expression of genes such as CD36 and FABP4 in melanoma may reduce the cellular internalization of fat and therefore make patients with melanoma less sensitive to a high dietary fat intake, explaining in part the obesity paradox observed in patients with melanoma.

Obesity and Its Impact on Outcomes in Patients With Stage III Colon Cancer Receiving Adjuvant Chemotherapy

BACKGROUND

Even though obesity is a well-established risk factor for developing colon cancer, its prognostic value is not very well understood. The present study elucidated the effect of obesity, as measured by the body mass index (BMI) and body surface area (BSA), on colon cancer outcomes.

PATIENTS AND METHODS

Patients with a diagnosis of stage III colon cancer from 2011 to 2016 who had undergone adjuvant chemotherapy in Alberta, Canada were identified. The demographic variables, treatment characteristics, and survival data were collected from the electronic medical records. Obesity was defined using the BMI in accordance with the World Health Organization criteria, and BSA was categorized as ≤ 2.0 m² (low) and > 2.0 m² (high). The effect of BMI and BSA on 5-year cancer-specific survival (CSS) and overall survival (OS) was analyzed using univariate and multivariate analysis.

RESULTS

A total of 915 patients were identified with a median age of 64 years. Of these, 37% were overweight or obese, and the BSA was high in 42% of the patients. The survival outcomes for the obese and underweight patients were not significantly different from those with a normal BMI (P = .61 and P = .30 for OS and CSS, respectively). Similarly, no correlation was found between BSA and OS or CSS. Although 21% of patients experienced a > 10-week delay in receiving adjuvant chemotherapy, neither BMI nor BSA correlated significantly with chemotherapy timing (P = .45).

CONCLUSIONS

Our results suggest that BMI and BSA do not correlate with survival outcomes in patients with stage III colon cancer. The role of a healthy lifestyle in an improved colon cancer prognosis might not be driven by its effects on obesity.

A Phase IIa Trial of Metformin for Colorectal Cancer Risk Reduction among Individuals with History of Colorectal Adenomas and Elevated Body Mass Index

Obesity is associated with risk of colorectal adenoma (CRA) and colorectal cancer. The signaling pathway activated by metformin (LKB1/AMPK/mTOR) is implicated in tumor suppression in Apc^Min/+ mice via metformin-induced reduction in polyp burden, increased ratio of pAMPK/AMPK, decreased pmTOR/mTOR ratio, and decreased pS6^Ser235/S6^Ser235 ratio in polyps. We hypothesized that metformin would affect colorectal tissue S6^Ser235 among obese patients with recent history of CRA. A phase IIa clinical biomarker trial was conducted via the U.S. National Cancer Institute-Chemoprevention Consortium. Nondiabetic, obese subjects (BMI ≥30) ages 35 to 80 with recent history of CRA were included. Subjects received 12 weeks of oral metformin 1,000 mg twice every day. Rectal mucosa biopsies were obtained at baseline and end-of-treatment (EOT) endoscopy. Tissue S6^Ser235 and Ki-67 immunostaining were analyzed in a blinded fashion using Histo score (Hscore) analysis. Among 32 eligible subjects, the mean baseline BMI was 34.9. Comparing EOT to baseline tissue S6^Ser235 by IHC, no significant differences were observed. Mean (SD) Hscore at baseline was 1.1 (0.57) and 1.1 (0.51) at EOT; median Hscore change was 0.034 (P = 0.77). Similarly, Ki-67 levels were unaffected by the intervention. The adverse events were consistent with metformin's known side-effect profile. Among obese patients with CRA, 12 weeks of oral metformin does not reduce rectal mucosa pS6 or Ki-67 levels. Further research is needed to determine what effects metformin has on the target tissue of origin as metformin continues to be pursued as a colorectal cancer chemopreventive agent.

Effects of high-fat diet-induced adipokines and cytokines on colorectal cancer development

Colorectal cancer (CRC) is the third most common tumor worldwide, and recent epidemiological studies have indicated that obesity contributes to the morbidity and mortality of CRC. Furthermore, obesity‐related adipokines have been shown to be closely related to the incidence of CRC, but the underlying mechanisms are unclear. Here, we investigated the effects of high‐fat diet‐induced adipokines and cytokines on the development of CRC in vitro and in vivo. For the in vivo assays, we divided 2‐week‐old C57BL/6J‐ApcMin/J male mice into three groups: normal‐fat diet (ND), high‐fat and high‐sugar feed (HFHS), and high‐fat and low‐sugar feed (HFLS). After 1 week, all mice were injected with 20 mg·kg⁻¹ 1,2‐dimethylhydrazine once weekly for 10 consecutive weeks. Body weight, liver weight, epididymal fat weight and blood glucose levels were greatly increased in HFHS and HFLS groups compared with the ND group, and the expression levels of some adipokines and cytokines were obviously higher in HFHS or HFLS mice compared with ND mice. For the in vitro assays, HCT116 CRC cells were treated with sera of ND, HFHS or HFLS groups, or serum‐free media as a negative control. We observed that sera derived from HFHS or HFLS mice that contain excess adipokines and cytokines promoted the proliferation, migration and invasion of HCT116 cells compared with the ND sera‐conditioned medium or serum‐free medium group. Therefore, high‐fat diet‐induced adipokines and cytokines may promote the progression of CRC in vivo and in vitro.

We investigated the effects of high‐fat diet‐induced adipokines and cytokines in the development of colorectal cancer. Some adipokines and cytokines were obviously higher in obese mice than in normal mice. Obesity‐induced adipokines and cytokines promoted the proliferation, migration and invasion of HCT116 cells. Therefore, high‐fat diet‐induced adipokines and cytokines may accelerate the progression of colorectal cancer.

Morbid Obesity Is Associated With an Increased Risk of Wound Complications and Infection After Lower Extremity Soft-tissue Sarcoma Resection

BACKGROUND

Obesity is associated with wound complications after lower extremity surgery. Excision of soft-tissue sarcomas is urgent, and unlike the elective surgery, obesity cannot be modified preoperatively. The purpose of this study was to evaluate the effect of obesity on treatment outcome.

METHODS

Six hundred fifty-three patients (343 men; mean age, 56 ± 18 years) with a lower extremity soft-tissue sarcoma were reviewed. The mean body mass index (BMI) was 27.1 ± 5.7 kg/m, with 189 obese patients (29%) having a BMI of ≥30 kg/m and 27 morbidly obese patients (4%) having a BMI of ≥40 kg/m. Complications and functional and oncologic outcomes were compared between groups.

RESULTS

Two hundred eighty-five patients (40%) sustained a postoperative complication, most commonly a dehiscence (n = 175; 24%) and infection (n = 147; 21%). On multivariate analysis, morbid obesity was associated with wound complications (P = 0.002) and infection (P = 0.01). Morbid obesity was not associated with local tumor recurrence (P = 0.56). No difference was found in the mean Toronto Extremity Salvage Score (P = 0.11) or Musculoskeletal Tumor Society (P = 0.41) scores between the groups.

DISCUSSION

Morbid obesity was associated with postoperative wound complications and infection. However, after surgery, obese patients can expect no difference in oncologic outcome, with an excellent functional result.

Adult Overweight and Survival from Breast and Colorectal Cancer in Swedish Women

BACKGROUND

The impact of overweight duration and intensity during adulthood on the prognosis after a cancer diagnosis remains largely unknown. We investigated this association in Swedish women with breast and colorectal cancer.

METHODS

A cohort of 47,051 women from the Swedish Lifestyle and Health Study was included, of whom 1,241 developed postmenopausal breast (mean age at diagnosis, 57.5 years) and 259 colorectal (mean age at diagnosis, 59.1 years) cancer. Trajectories of body mass index (BMI) between ages 20 and 50 years were estimated for the full cohort using a quadratic growth model and studied in relation to risk of death from any cause using multivariate Cox regression models among cancer survivors.

RESULTS

Compared with patients with cancer who were never overweight (BMI < 25) during early adulthood (ages 20-50 years), the risk of early death from breast cancer increased by 3% [hazard ratio (HR) = 1.03; 95% confidence interval (CI), 1.01-1.05] and from colorectal cancer by 4% (HR = 1.04; 95% CI, 1.01-1.06) for every year lived with overweight. A higher intensity of overweight (i.e., a combination of duration and degree of overweight-a concept comparable to pack-years of cigarette smoking) further increased the risk of dying in this population. Although risks were slightly more pronounced for women diagnosed with late-stage breast cancer, no clear association was found for colorectal cancer.

CONCLUSIONS

Our results suggest that adulthood overweight duration and intensity have a long-lasting influence on breast and colorectal cancer survival.

IMPACT

Our study highlights the need for effective prevention of overweight and obesity starting at an early age.

Obesity and cancer: A mechanistic overview of metabolic changes in obesity that impact genetic instability

Obesity, defined as a state of positive energy balance with a body mass index exceeding 30 kg/m2 in adults and 95th percentile in children, is an increasing global concern. Approximately one-third of the world's population is overweight or obese, and in the United States alone, obesity affects one in six children. Meta-analysis studies suggest that obesity increases the likelihood of developing several types of cancer, and with poorer outcomes, especially in children. The contribution of obesity to cancer risk requires a better understanding of the association between obesity-induced metabolic changes and its impact on genomic instability, which is a major driving force of tumorigenesis. In this review, we discuss how molecular changes during adipose tissue dysregulation can result in oxidative stress and subsequent DNA damage. This represents one of the many critical steps connecting obesity and cancer since oxidative DNA lesions can result in cancer-associated genetic instability. In addition, the by-products of the oxidative degradation of lipids (e.g., malondialdehyde, 4-hydroxynonenal, and acrolein), and gut microbiota-mediated secondary bile acid metabolites (e.g., deoxycholic acid and lithocholic acid), can function as genotoxic agents and tumor promoters. We also discuss how obesity can impact DNA repair efficiency, potentially contributing to cancer initiation and progression. Finally, we outline obesity-related epigenetic changes and identify the gaps in knowledge to be addressed for the development of better therapeutic strategies for the prevention and treatment of obesity-related cancers.

Diabetes, Obesity, and the Metabolic Syndrome as Prognostic Factors in Stages I to III Colorectal Cancer Patients

BACKGROUND

Attempts to introduce prognostic factors for survival outcomes in localized colorectal cancer patients receiving surgical treatment with or without adjuvant therapies, beyond the classic staging parameters, have been met with limited success. Obesity and diabetes mellitus are among the conditions that predispose to colorectal cancer but their value as prognostic markers once the disease is diagnosed is controversial.

PATIENTS AND METHODS

This study examines the prognostic value of the components of metabolic syndrome in a retrospective series of colorectal cancer patients with stages I to III disease followed in a single center.

RESULTS

Among the four components of the metabolic syndrome, only diabetes was independently associated with progression-free survival (PFS) while obesity, hypertension, and dyslipidemia were not. No associations of the metabolic syndrome (MS) or its components with overall survival (OS) were observed in multivariate analysis.

CONCLUSION

These data pinpoint to diabetes mellitus (DM) as a possible prognostic factor for PFS in localized colorectal cancer and further cast doubt for the value of obesity as measured by body mass index (BMI) on local stage colorectal cancer prognosis.

Adipocyte and lipid metabolism in cancer drug resistance

Development of novel and effective therapeutics for treating various cancers is probably the most congested and challenging enterprise of pharmaceutical companies. Diverse drugs targeting malignant and nonmalignant cells receive clinical approval each year from the FDA. Targeting cancer cells and nonmalignant cells unavoidably changes the tumor microenvironment, and cellular and molecular components relentlessly alter in response to drugs. Cancer cells often reprogram their metabolic pathways to adapt to environmental challenges and facilitate survival, proliferation, and metastasis. While cancer cells' dependence on glycolysis for energy production is well studied, the roles of adipocytes and lipid metabolic reprogramming in supporting cancer growth, metastasis, and drug responses are less understood. This Review focuses on emerging mechanisms involving adipocytes and lipid metabolism in altering the response to cancer treatment. In particular, we discuss mechanisms underlying cancer-associated adipocytes and lipid metabolic reprogramming in cancer drug resistance.

Correlation between Colon Polyps and Metabolic Syndrome and HP Infection Status

Background

This study investigated the relationships among the characteristics of colon polyps and potential risk factors, including metabolic condition, CEA level, uric acid level, and Helicobacter pylori (Hp) infection status.

Method

Clinical data from patients who received colonoscopy were collected and analyzed, including patients' gender, age, polyp pathology, metabolic syndrome (MS) status, CEA level, uric acid level, and Hp infection status. Patients were divided into a polyp group and a control group based on whether they presented with colon polyps. Then, clinical data were compared between the two groups to identify any differences between the groups and their relationships to colon polyps.

Result

Compared with the control group, the polyp group had significant differences in patient gender, body mass index (BMI), waistline, blood pressure, fasting blood glucose level, blood lipid level, and uric acid level (p < 0.05), but there were no significant differences in LDL and CEA levels (p > 0.05). Patients with MS or a uric acid level > 340 mg/dl had a greater tendency to develop colon polyps but this was not statistically significant.

Conclusion

The incidence of colon polyps may be associated with MS and uric acid levels, but further studies are warranted to confirm this conclusion.

Dietary intake of fiber, whole grains and risk of colorectal cancer: An updated analysis according to food sources, tumor location and molecular subtypes in two large US cohorts

Epidemiologic evidence relating fiber intake to colorectal cancer (CRC) remains inconclusive and data are limited on different food sources of fiber and heterogeneity by tumor subsite and molecular profile. We prospectively followed for CRC incidence 90,869 women from the Nurses' Health Study (1980-2012) and 47,924 men from the Health Professionals Follow-up Study (1986-2012), who completed a validated food frequency questionnaire every 4 years. Cox proportional hazards regression was used to examine the associations with CRC risk for total, cereal, fruit and vegetable fiber and whole grains. We also assessed the associations according to tumor subsites (proximal colon, distal colon and rectum) and molecular markers (microsatellite instability, BRAF mutation, CpG island methylator phenotype and KRAS mutation). We documented 3,178 CRC cases during 3,685,903 person-years of follow-up in the NHS and HPFS. Intake of total dietary fiber was not associated with CRC risk after multivariable adjustment in either women (hazard ratio [HR] comparing extreme deciles, 1.17; 95% CI, 0.92-1.48, p_trend = 0.55) or men (HR, 0.90; 95% CI, 0.67-1.21, p_trend = 0.47). Higher intake of cereal fiber and whole grains was associated with lower CRC risk in men with an HR of 0.75 (95% CI, 0.57-1.00) and 0.72 (95% CI, 0.54-0.96), respectively. No heterogeneity was detected by tumor subsite or molecular markers (p_{heterogeneity}  > 0.05). Higher intake of total dietary fiber within the range of a typical American diet is unlikely to substantially reduce CRC risk. The potential benefit of cereal fiber and whole grains in men warrants further confirmation.

Semiautomated Measure of Abdominal Adiposity Using Computed Tomography Scan Analysis

BACKGROUND

The obesity epidemic has prompted the need to better understand the impact of adipose tissue on human pathophysiology. However, accurate, efficient, and replicable models of quantifying adiposity have yet to be developed and clinically implemented. We propose a novel semiautomated radiologic method of measuring the visceral fat area (VFA) using computed tomography scan analysis.

MATERIALS AND METHODS

We obtained a cohort of 100 patients with rectal adenocarcinoma, with a median age of 60.9 y (age range: 35-87 y) and an average body mass index of 28.8 kg/m2 ± 6.56 kg/m2. The semiautomated quantification method of adiposity was developed using a commercial imaging suite. The method was compared to two manual delineations performed using two different picture archiving communication systems. We quantified VFA, subcutaneous fat area (SFA), total fat area (TFA), and visceral-to-subcutaneous fat ratio (V/S ratio) on computed tomography axial slices that were at the L4-L5 intervertebral level.

RESULTS

The semiautomated method was comparable to manual measurements for TFA, VFA, and SFA with intraclass correlation (ICC) of 0.99, 0.97, and 0.96, respectively. However, the ICC for the V/S ratio was only 0.44, which led to the identification of technical outliers that were identified using robust regression. After removal of these outliers, the ICC improved to 0.99 for TFA, VFA, and SFA and 0.97 for the V/S ratio. Measurements from the manual methodology highly correlated between the two picture archiving communication system platforms, with ICC of 0.98 for TFA, 0.98 for VFA, 0.96 for SFA, and 0.95 for the V/S ratio.

CONCLUSIONS

This semiautomated method is able to generate precise and reproducible results. In the future, this method may be applied on a larger scale to facilitate risk stratification of patients using measures of abdominal adiposity.

The metabolic syndrome and its components as prognostic factors in metastatic colorectal cancer

BACKGROUND

Components of the metabolic syndrome (MetS) are involved in colorectal cancer development and the incidence of the disease is higher in obese and diabetic patients. Nevertheless, the value of these diseases or the MetS as a whole as prognostic markers once colorectal cancer is diagnosed is controversial.

METHODS

Patients with metastatic colorectal cancer treated in our center over a 6-year period were reviewed and data on baseline characteristics of the patients and their cancers were extracted. Data on the presence and pharmacologic treatments of the four components of the MetS (obesity, diabetes, hypertension, and dyslipidemia) were also recorded. Overall survival (OS) and progression-free survival (PFS), Kaplan-Meier curves of the various groups were constructed and compared with the log-rank test.

RESULTS

One hundred and twenty-three patients were included in the analysis. The prevalence of the four MetS components was 66.1% for overweight/obesity, 25.2% for diabetes, 61% for hypertension, and 41.5% for dyslipidemia. Among the four components of the metabolic syndrome, none was associated with either PFS or OS. Diabetes tended to approach significance for PFS (p = 0.08). The MetS as a whole did not influence survival outcome. MetS was not prognostic even if the overweight category was not considered as a positive element of the syndrome.

CONCLUSION

These data suggest that diabetes or other metabolic syndrome elements are not prognostic factors for PFS or OS in metastatic colorectal cancer. Further investigation may be warranted with a focus on refinement of the metabolic evaluation.

Visceral Adipose Tissue Modulates Radiosensitivity in Oesophageal Adenocarcinoma

Oesophageal adenocarcinoma (OAC) is an exemplar model of obesity-associated cancer. Response to neoadjuvant chemoradiotherapy (NA CRT) is a clinical challenge. We examined if visceral adipose tissue and obesity status alter radiosensitivity in OAC. The radioresistant (OE33R) and radioresponsive (OE33P) OAC isogenic model was cultured with adipose tissue conditioned media from three patient cohorts: non-cancer patients, surgery only OAC patients and NA CRT OAC patients. Cell survival was characterised by clonogenic assay, metabolomic profiling by nuclear magnetic resonance spectroscopy and adipokine receptor gene expression by qPCR. A retrospective in vivo study compared tumour response to NA CRT in normal weight (n=53) versus overweight/obese patients (n=148). Adipose conditioned media (ACM) from all patient cohorts significantly increased radiosensitivity in radioresistant OE33R cells. ACM from the NA CRT OAC cohort increased radiosensitivity in OE33P cells. Metabolomic profiling demonstrated separation of the non-cancer and surgery only OAC cohorts and between the non-cancer and NA CRT OAC cohorts. Gene expression profiling of OE33P versus OE33R cells demonstrated differential expression of the adiponectin receptor-1 (AR1), adiponectin receptor-2 (AR2), leptin receptor (LepR) and neuropilin receptor-1 (NRP1) genes. In vivo overweight/obese OAC patients achieved an enhanced tumour response following NA CRT compared to normal weight patients. This study demonstrates that visceral adipose tissue modulates the cellular response to radiation in OAC.

Obesity and cardiovascular risk in an oncology day ward population

INTRODUCTION

The burden of obesity and risk of cardiovascular (CV) disease amongst an oncology population receiving active treatment is ill-defined. We performed a retrospective analysis assessing the incidence of obesity and cardiovascular (CV) risk factors in this group (grp) of patients as well as the predicted 10-year risk of a CV event.

METHODS

Data from all patients (pts) receiving intravenous chemotherapy in an Irish oncology satellite unit over an 18-month period was extracted from chemotherapy prescriptions and electronic patient records. To calculate patients' 10-year risk of developing CV disease, we used QRISK, a predictive risk calculator.

RESULTS

The prevalence of obesity (BMI > 30) amongst the total population was 19% (n = 21), with 26% (n = 28) overweight (BMI, 25-< 30). Information on CV risk factors was available in 93 pts. with the following rates being observed: hypertension 34%, dyslipidaemia 19%, current smoker 18% and diabetes 11%. The average 10-year risk of a CV event (stroke/MI) in this cohort was 19.2% (± 16.6), with a relative risk of 1.4 compared to their age-matched controls without CV risk factors.

CONCLUSIONS

We observed similar or lower rates of obesity and CV risk factors in this cohort compared to the general adult Irish population. The average predicted risk of developing CV disease in this grp was moderate to high. This can have significant future implications with regard to cancer survivorship, disease recurrence and suitability for further oncological treatments.

Obesity and gastrointestinal cancer: the interrelationship of adipose and tumour microenvironments

Increasing recognition of an association between obesity and many cancer types exists, but how the myriad of local and systemic effects of obesity affect key cellular and non-cellular processes within the tumour microenvironment (TME) relevant to carcinogenesis, tumour progression and response to therapies remains poorly understood. The TME is a complex cellular environment in which the tumour exists along with blood vessels, immune cells, fibroblasts, bone marrow-derived inflammatory cells, signalling molecules and the extracellular matrix. Obesity, in particular visceral obesity, might fuel the dysregulation of key pathways relevant to both the adipose microenvironment and the TME, which interact to promote carcinogenesis in at-risk epithelium. The tumour-promoting effects of obesity can occur at the local level as well as systemically via circulating inflammatory, growth factor and metabolic mediators associated with adipose tissue inflammation, as well as paracrine and autocrine effects. This Review explores key pathways linking visceral obesity and gastrointestinal cancer, including inflammation, hypoxia, altered stromal and immune cell function, energy metabolism and angiogenesis.

Higher visceral fat area/subcutaneous fat area ratio measured by computed tomography is associated with recurrence and poor survival in patients with mid and low rectal cancers

PURPOSE

Obesity is thought to influence postoperative complications and recurrence of mid and low rectal cancer (MLRC) because of intraoperative technical difficulties. However, few reports have described the relationship between obesity indices and the clinical outcomes of MLRC. This study aimed to investigate the association between visceral obesity on computed tomography (CT) and oncolofical outcomes after surgery for MLRC and identify the obesity index that most accurately reflects clinical outcomes.

METHODS

We investigated 125 patients who underwent curative resection for MLRC between 2004 and 2010. Visceral fat area (VFA) was defined as the umbilicus-level intra-abdominal adipose tissue area measured by CT. Body mass index (BMI), total fat area, VFA, subcutaneous fat area (SFA) and VFA/SFA ratio (V/S ratio) were analysed.

RESULTS

The median follow-up time was 60.3 months (range, 38.2-122.6 months). Recurrence was detected in 28 (22.4%) patients. Among the various obesity indices, recurrence was significantly associated with V/S ratio only (1.02 ± 0.45 versus 0.86 ± 0.34; P = 0.046). Stage, preoperative carcinoembryonic antigen level, V/S ratio, lymphatic invasion and perineural invasion were significantly associated with recurrence on univariate analysis, while only V/S ratio (P = 0.019; 95% confidence interval, 1.22 to 9.09) was significantly associated with recurrence on multivariate analysis. Disease-free and overall survival of the obese group (V/S ratio > 1.0) were shorter than those of the non-obese group.

CONCLUSIONS

V/S ratio is the optimal obesity index for predicting stage I-III MLRC recurrence.

The role of metabolic syndrome variant in the malignant tumors progression

Metabolic syndrome (MS) is one of the leading risk factors for the development of some common cancers (endometrial cancer, postmenopausal breast cancer, colorectal cancer). Currently, a drug-induced metabolic syndrome related with androgen deprivation therapy in patients with prostate cancer represents a serious medical problem. Not only MS, or its individual components, but MS variants with different levels of leptin, adiponectin, visfatin, resistin are associated with tumor invasion, metastasis and survival rates in patients with MS-associated malignancies.

A comprehensive look at the role of hyperlipidemia in promoting colorectal cancer liver metastasis

Colorectal cancer (CRC) is one of the most malignant cancers, and it tends to migrate to the liver and has a high mortality rate. Several mechanisms behind the metastasis of CRC have been identified, including hyperlipidemia. For example, hyperlipidemia can lead to enhanced stemness and neutrophil infiltration, which increases CRC metastasis. There are three primary aspects to the relationship between hyperlipidemia and CRC metastasis: hyperlipidemia (1) promotes the initial metastatic properties of CRC, (2) stimulates CRC cells to leave the vasculature, and (3) facilitates the development of CRC metastasis. In this study, we provide a comprehensive overview of the role that hyperlipidemia played in CRC metastasis to help reduce the mortality associated with CRC metastasis from the standpoint of metabolic. We also review cancer metastasis.

Obesity is associated with larger soft-tissue sarcomas, more surgical complications, and more complex wound closures (obesity leads to larger soft-tissue sarcomas)

BACKGROUND AND OBJECTIVES

Does a link exist between obesity and soft-tissue sarcoma outcomes? We hypothesized that soft-tissue sarcomas in patients with obesity may lead to larger tumors at detection, with an increased risk for a more complex surgical excision, wound healing-related complications, higher stage at presentation, and decreased survival.

METHODS

One hundred thirty-nine and patients with soft-tissue sarcoma were retrospectively evaluated over 10 years. Patients were divided into 2 cohorts based on the World Health Organization body mass index (BMI) obesity grouping. A BMI ≥ 30 kg/m² was classified as obese and a BMI < 30 kg/m² was classified as nonobese.

RESULTS

Eighty-five nonobese and 54 obese individuals were evaluated. The median tumor diameter was 50% larger (P = .024) and the overall complication rate was 1.7-fold higher in patients with obesity (P = .0032). Patients with obesity also had a statistically significantly higher rate of complex wound closures. In multivariable logistic regression, obesity remained a highly significant factor favoring complications after the surgical treatment of soft-tissue sarcoma (odds ratio = 3.66, 95% confidence interval = 1.54-8.71; P = .0033). No statistically significant differences were noted on comparing groups for the incidence of metastatic spread or survival.

CONCLUSIONS

These findings suggest that obesity is associated with larger tumors, a higher incidence of wound complications, and greater use of complex wound-closure methods.

Obesity-associated miR-27a upregulation promotes hepatocellular carcinoma metastasis through suppressing SFRP1

Background

Obesity was a recognized risk factor for the development and progression of hepatocellular carcinoma (HCC). However, the effects and mechanisms by which obesity promotes HCC metastasis remain poorly understood.

Materials and methods

We cultured adipocyte induced by preadipocyte 3T3-L1 in vitro and established HCC metastasis model in obesity mouse in vivo to mimic the tumor microenvironment in obese status. The mechanisms underlying obesity-associated miR-27a upregulation promoting HCC metastasis were investigated.

Results

In this study, we showed that miR-27a was upregulated in adipocytes, obese mouse model and clinical samples, and the increased miR-27a level promoted migration and invasion in HCC cells, increased the number of metastasis nodes in obese mouse model, and was associated with poor clinical outcomes. Overexpressed secreted frizzled-related protein 1 in HCC cells and tissues significantly alleviated the upregulation of β-catenin and matrix metalloproteinase-7 induced by high level of miR-27a. Meanwhile, the E-cadherin expression decreased and Vimentin expression increased, linking with high level of β-catenin in high-fat group.

Conclusion

Taken together, our results have elucidated the critical role of extracellular miR-27a as a pro-metastatic factor in HCC and revealed that obesity-associated miR-27a upregulation promoted HCC metastasis through activated Wnt/β-catenin signaling by suppressing secreted frizzled-related protein 1. Our findings shed light on the novel mechanism underlying HCC metastasis and provided miR-27a as a promising target for obese liver cancer therapy.

Dietary Walnuts Protect Against Obesity-Driven Intestinal Stem Cell Decline and Tumorigenesis

Obesity can negatively impact intestinal homeostasis, and increase colon cancer risk and related mortality. Thus, given the alarmingly high rates of obesity in the US and globally, it is critical to identify practical strategies that can break the obesity-cancer link. Walnuts have been increasingly recognized to mitigate cancer risk, and contain many bioactive constituents with antioxidant and anti-inflammatory properties that could potentially counteract pathways thought to be initiators of obesity-related cancer. Therefore, the purpose of this study was to determine if walnuts could preserve intestinal homeostasis, and attenuate tumorigenesis and growth in the context of obesity and a high calorie diet. To this end, we studied effects of walnuts on these parameters under different dietary conditions in wildtype mice, two independent Apc models (Apc^1638N/+ and Apc^Δ14), and in MC38 colon cancer cells in vivo, respectively. Walnuts did not alter the metabolic phenotype or intestinal morphology in normal mice fed either a low-fat diet (LFD), LFD with 6% walnuts (LFD+W), high-fat diet (HFD), or HFD with 7.6% walnuts (HFD+W). However, walnuts did lead to a significant reduction in circulating CCL5 and preserved intestinal stem cell (ISC) function under HFD-fed conditions. Furthermore, walnuts reduced tumor multiplicity in Apc^1638N/+ male HFD+W animals, as compared to HFD controls (3.7 ± 0.5 vs. 2.5 ± 0.3; P = 0.015), tended to reduce the number of adenocarcinomas (0.67 ± 0.16 vs. 0.29 ± 0.12; P = 0.07), and preferentially limited tumor growth in Apc^Δ14 male mice (P = 0.019) fed a high-calorie western-style diet. In summary, these data demonstrate that walnuts confer significant protection against intestinal tumorigenesis and growth and preserve ISC function in the context of a high-calorie diet and obesity. Thus, these data add to the accumulating evidence connecting walnuts as a potentially effective dietary strategy to break the obesity-colon cancer link.

Insulin promotes progression of colon cancer by upregulation of ACAT1

Background

Insulin resistant and the progression of cancer is closely related. The aim of this study was to  investigate the effect of insulin on the proliferation and migration of colon cancer cells and its underlying mechanism.

Methods

Colon carcinoma tissues from the 80 cases of colon cancer patients were collected. Immunohistochemistry was used to detect the expression of acyl coenzyme A: cholesterol acyltransferase1 (ACAT1), and we analyzed the correlation between hyperglycemia and ACAT1, hyperglycemia and metastasis. CCK8 assay and transwell assay were used to investigate the effect of different concentrations of insulin and ACAT1siRNA on human colon cancer cell line HT-29. ACAT1 mRNA expression and protein level in HT-29 cells were determined by real-time quantitative PCR and western blotting, respectively.

Results

Biopsies from patients with colon carcinoma showed hyperglycemia links ACAT1, lymph nodes metastasis and distant metastasis. Insulin markedly promoted cell proliferation and migration in human colon cancer HT-29 cells. Moreover, ACAT1mRNA expression and protein level were increased by insulin. ACAT1siRNA resulted in a complete inhibition of the ACAT1 mRNA expression. Consequently insulin-triggered cell proliferation and migration on colon cancer cells were inhibited.

Conclusion

The progression of colon cancer has a positive correlation with hyperinsulinemia. Insulin-triggered cell proliferation and metastatic effects on colorectal cancer cells are mediated by ACAT1. Therefore, insulin could promote colon cancer progression by upregulation of ACAT1, which maybe is a potential therapeutic target for colon cancer.